As an automotive continuously variable transmission, there is known a continuously variable transmission as shown in FIG. 8 which comprises a drive pulley (2), having a fixed sheave (2a) and a movable sheave (2b) and provided on an engine's side, a driven pulley (3), having a fixed sheave (3a) and a movable sheave (3b) and provided on a drive wheels' side, and an endless power transmission chain (1) extended between the two pulleys and in which the chain (1) is clamped by means of hydraulic pressure by causing the movable sheaves (2b)(3a) to move towards or away from the fixed sheaves (2a)(3b) by a hydraulic actuator, so that a contact load is generated between the pulleys (2)(3) and the chain (1) by virtue of the clamping force to thereby transmit torque by friction force at the contact portion.
As the power transmission chain, Patent Document 1 proposes a power transmission chain which comprises a plurality of links having front and rear inserting portions through which pins are inserted, and a plurality of first pins and a plurality of second pins for connecting together the links which are aligned in a chain width direction so that the front inserting hole of one link corresponds to the rear inserting hole of the other link so as to allow the links to bend relative to each other in a length direction, wherein the first pin which is fixed in the front inserting portion of one link and is movably fitted in the rear inserting hole in the other link and the second pin which is movably fitted in the front inserting hole in one link and is fixed in the rear inserting hole in the other link are brought into rolling contact motion relative to each other to thereby enable the links to bend relative to each other in the length direction, and to reduce noise and vibration, it is proposed to have two or more pitch lengths of the links, rolling contact surface shapes of the pins and contact positions (offset amounts) of the pins with surfaces of the pulleys.
Patent Document 1: JP-2006-242374